The present invention relates to a digital signal recording and/or reproducing apparatus for recording and/or reproducing digital video/audio signals, for example, by using slant tracks formed by a rotary head and a digital signal recording and/or reproducing method thereof.
There is a digital signal recording and/or reproducing apparatus for recording and/or reproducing digital video/audio signals by using slant tracks formed by a rotary head. Such digital signal recording and/or reproducing apparatus uses a recording format of one track shown in FIG. 1A of the accompanying drawings when digital video/audio signals are recorded and/or reproduced.
A rotary head (not shown) scans a magnetic tape in the direction shown by an arrow x in FIG. 1A. In accordance with the scanning direction of the rotary head, there are provided an information signal (ITI: insert and track information) area, an audio signal area, a video signal area and a subcode signal area within one track. Margins are provided at the head tracing starting portion and the head tracing ending portion, respectively. Further, there are provided margins between respective areas.
According to this recording format, the audio signal area, the video signal area and the subcode signal area are arranged such that a so-called postrecording can be effected in the above-mentioned areas independently. Specifically, a reference signal that is used as a reference timing signal to switch the respective areas is provided in the ITI area. Then, the postrecording of each area is carried out by setting the apparatus to the recording mode at a timing of each area on the basis of the reference signal.
However, in the digital signal recording and/or reproducing apparatus using slant tracks formed by the rotary head, it is difficult to obtain an accurate linearity of the slant track. Specifically, it is frequently observed that a slant track is shaped in S-letter configuration of a positive or opposite polarity as shown in FIG. 1B. In this case, if a recording apparatus and a reproducing apparatus are different in polarity of S-letter in slant track, there is then the risk that the recording apparatus and the reproducing apparatus are not compatible with each other in use.
In the digital signal recording and/or reproducing apparatus, a displacement between the rotary head and the slant track (tracking displacement) is constantly observed and the tracking is corrected by controlling the travel of the recording medium (magnetic tape) so that displacements of the whole slant track are averaged.
However, in the digital signal recording and/or reproducing apparatus, when the slant track, for example, is shaped in S letter as shown by a solid line in FIG. 1B and the scanning locus of the rotary head is shaped as an inverse S letter as shown by a dashed line in FIG. 1B, if the tracking is corrected so that the displacements of the whole track are averaged (as shown by a one-dot chain line in FIG. 1B), a positional relationship between the slant track and the scanning locus becomes as shown in FIG. 1B. FIG. 1B shows this positional relationship in a little exaggerated fashion.
In that case, if the postrecording of the subcode signal area is carried out, the subcode signal area is recorded at the position shown by a dashed hatching in FIG. 1B and a displacement a is generated in these tracking operations with the result that a continuity cannot be obtained.